Dual-pressure gas turbine waste heat boiler capable of adjusting steam flow

Abstract

The utility model discloses a dual-pressure gas turbine waste heat boiler capable of adjusting steam flow, which comprises a boiler flue, and a second high-pressure superheater, a first high-pressure superheater, a high-pressure evaporator, a low-pressure superheater, a high-pressure economizer, a low-pressure evaporator and a low-pressure economizer are sequentially arranged in the boiler flue. The low-pressure superheater communicates with a turbine low-pressure cylinder and an industrial gas connector through a low-pressure main steam pipeline, and the second high-pressure superheater communicates with a turbine high-pressure cylinder through a high-pressure main steam pipeline. The desuperheater is arranged on the low-pressure main steam pipeline, the high-pressure main steam pipeline is connected with the low-pressure main steam pipeline through the pipeline, the shut-off valve and the adjusting valve are arranged in the pipeline, and the low-pressure main steam flow and temperature requirements can be adjusted and controlled by adjusting the opening degree of the adjusting valve and the desuperheater. Therefore, the flow and the temperature of the low-pressure main steam are adjusted to meet the industrial steam demand.

Description

Technical Field

[0001] This utility model relates to the field of waste heat boiler heating technology, and more particularly to a dual-compression gas turbine waste heat boiler with adjustable steam flow, which is suitable for dynamic distribution and parameter control of high and low pressure main steam in a combined heat and power system. Background Technology

[0002] In combined cycle cogeneration, the waste heat boiler recovers waste heat from the gas turbine exhaust, generating steam to drive the turbine for power generation, while also producing low-parameter steam for industrial production. When there is a heating demand, part of the system's steam is used for heating, and the rest is used for power generation; when there is no heating demand, all the steam from the waste heat boiler is used for turbine power generation.

[0003] The gas turbine waste heat boiler steam-water system includes heat exchange tube bundles, containers, and auxiliary equipment such as steam drum, economizer, evaporator, superheater, header, desuperheater, valves, and water pumps.

[0004] Gas turbine waste heat boilers utilize the exhaust heat from gas turbines to heat water, simultaneously producing relatively independent steam with different parameters. However, the steam parameters and production capacity of a gas turbine waste heat boiler depend entirely on the parameters and flow rate of the gas turbine exhaust; the boiler itself lacks the means to regulate steam flow. In some combined heat and power (CHP) projects, high-pressure steam is typically used entirely for turbine power generation, while low-pressure steam is used for industrial production or turbine power generation as needed. Industrial production requires stable steam flow and other parameters. When the gas turbine load is low, the demand for low-pressure heating steam flow is high or requires constant flow, or when industrial production lines are upgraded and adjusted, increasing the steam flow, pressure, and temperature requirements, conventional gas turbine waste heat boiler systems struggle to meet these demands.

[0005] After the high-pressure main steam is depressurized, it is introduced into the low-pressure main steam header and mixed with the low-pressure steam generated by the boiler. This allows for automatic adjustment of the distribution of high and low-pressure steam flow. Since the low-pressure main steam is used for heating, a desuperheater is installed at the end of the low-pressure main steam pipeline to maintain the stability of the heating steam temperature when the load of the gas turbine changes. This effectively solves the problem of stabilizing parameters such as the heating steam flow rate in combined cycle cogeneration. Utility Model Content

[0006] To solve the above-mentioned technical problems, this utility model designs a dual-compression gas turbine waste heat boiler with adjustable steam flow.

[0007] The present invention adopts the following technical solution:

[0008] A dual-pressure gas turbine waste heat boiler with adjustable steam flow includes a boiler flue. Within the flue, a high-pressure superheater II, a high-pressure superheater I, a high-pressure evaporator, a low-pressure superheater, a high-pressure economizer, a low-pressure evaporator, and a low-pressure economizer are sequentially arranged. The low-pressure feedwater inlet is connected to the low-pressure economizer via a pipeline. The low-pressure economizer is connected to the low-pressure boiler drum. The water outlet of the low-pressure boiler drum is connected to the low-pressure evaporator via a downcomer. The low-pressure evaporator is connected to the low-pressure boiler drum via a riser. The steam outlet of the low-pressure boiler drum is connected to the low-pressure superheater. The low-pressure superheater is connected to the turbine's low-pressure main steam pipeline. The cylinder and industrial gas interface are connected. The low-pressure boiler drum is connected to the high-pressure economizer via pipeline. The high-pressure economizer is connected to the high-pressure boiler drum. The water outlet of the high-pressure boiler drum is connected to the high-pressure evaporator via a downcomer. The high-pressure evaporator is connected to the high-pressure boiler drum via a riser. The steam outlet of the high-pressure boiler drum is connected to the first high-pressure superheater. The first high-pressure superheater is connected to the second high-pressure superheater. The second high-pressure superheater is connected to the high-pressure cylinder of the turbine via the high-pressure main steam pipeline. The low-pressure main steam pipeline is equipped with a desuperheater. The high-pressure main steam pipeline and the low-pressure main steam pipeline are connected by a pipeline. The pipeline is equipped with a shut-off valve and a regulating valve.

[0009] Preferably, a check valve is provided on the low-pressure main steam pipeline.

[0010] Preferably, the desuperheater is connected to the low-pressure water supply inlet.

[0011] Preferably, a high-pressure water pump is installed on the pipeline connecting the low-pressure boiler drum and the high-pressure economizer.

[0012] Preferably, a chimney is connected to the tail end of the boiler flue.

[0013] The beneficial effects of this utility model are: (1) Under low-load conditions of the gas turbine, since a connecting pipe is set between the high-pressure main steam and the low-pressure main steam, and a shut-off valve and a regulating valve are set on the pipe, the high-pressure main steam is introduced into the low-pressure main steam pipe by opening the shut-off valve and the regulating valve, so as to increase the flow rate of the low-pressure main steam and solve the problem of insufficient flow rate of the low-pressure main steam; (2) Under the condition of constant gas turbine load, according to the industrial steam consumption requirements, the low-pressure main steam heating flow rate is adjusted by adjusting the opening of the regulating valve to match the industrial steam demand; (3) When the gas turbine exhaust temperature is low in winter, the low-pressure main steam temperature When the temperature is too low and does not meet the industrial gas demand, the high-temperature high-pressure main steam is mixed with the low-pressure main steam by adjusting the opening of the regulating valve, thereby increasing the temperature of the low-pressure main steam to meet the industrial steam demand; (4) When the industrial gas temperature changes or there is a demand for improvement, the shut-off valve and regulating valve are opened to allow the high-temperature high-pressure main steam to be introduced into the low-pressure main steam pipeline, and the temperature is adjusted by the desuperheater to meet the new steam parameter requirements; (5) When the turbine fails, the turbine inlet valve can be closed and the regulating valve can be fully opened to use all the steam for heating, thereby avoiding the shutdown of the entire system due to the turbine failure and improving the reliability of the system. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of this utility model;

[0015] In the diagram: 1. Boiler flue; 11. High-pressure superheater II; 12. High-pressure superheater I; 13. High-pressure evaporator; 14. High-pressure economizer; 15. High-pressure boiler drum; 2. Chimney; 21. Low-pressure superheater; 22. Low-pressure evaporator; 23. Low-pressure economizer; 24. Low-pressure boiler drum; 31. Check valve; 32. Shut-off valve; 33. Regulating valve; 34. Desuperheater; A. Flue gas inlet; B. Low-pressure feedwater inlet; C. High-pressure turbine cylinder; D. Low-pressure turbine cylinder; E. Industrial steam interface; F. High-pressure feedwater pump. Detailed Implementation

[0016] The technical solution of this utility model will be further described in detail below through specific embodiments and with reference to the accompanying drawings:

[0017] Example: Figure 1 As shown, a dual-pressure gas turbine waste heat boiler with adjustable steam flow includes a boiler flue 1. Within the boiler flue, a high-pressure superheater 21, a high-pressure superheater 12, a high-pressure evaporator 13, a low-pressure superheater 21, a high-pressure economizer 14, a low-pressure evaporator 22, and a low-pressure economizer 23 are sequentially arranged. The low-pressure feedwater inlet B is connected to the low-pressure economizer via a pipeline. The low-pressure economizer is connected to the low-pressure boiler drum 24. The water outlet of the low-pressure boiler drum is connected to the low-pressure evaporator via a downcomer. The low-pressure evaporator is connected to the low-pressure boiler drum via a riser. The steam outlet of the low-pressure boiler drum is connected to the low-pressure superheater. The low-pressure main steam pipeline of the low-pressure superheater is connected to the low-pressure cylinder D of the steam turbine and the industrial gas interface E. A check valve 31 and a desuperheater 34 are installed on the low-pressure main steam pipeline. Water from the low-pressure boiler drum is pumped by the high-pressure feedwater pump F and then connected to the high-pressure economizer via pipelines. The high-pressure economizer is connected to the high-pressure boiler drum 15. The water outlet of the high-pressure boiler drum is connected to the high-pressure evaporator via a downcomer. The high-pressure evaporator is connected to the high-pressure boiler drum via a riser. The steam outlet of the high-pressure boiler drum is connected to the high-pressure superheater 1. The high-pressure superheater 1 is connected to the high-pressure superheater 2. The high-pressure superheater 2 is connected to the high-pressure cylinder C of the steam turbine via the high-pressure main steam pipeline. The high-pressure main steam pipeline and the low-pressure main steam pipeline are connected by a pipeline, which includes a shut-off valve 32 and a regulating valve 33. A chimney 2 is connected to the tail end of the boiler flue 1.

[0018] When the adjustable flow waste heat boiler is in use, the high-temperature flue gas discharged from the gas turbine enters the boiler flue 1 from the flue gas inlet A, and passes through the heat exchange surfaces of high-pressure superheater 21, high-pressure superheater 12, high-pressure evaporator 13, low-pressure superheater 21, high-pressure economizer 14, low-pressure evaporator 22 and low-pressure economizer 23 in sequence before being discharged from the chimney 2.

[0019] Feedwater enters from the low-pressure feedwater inlet B, passes through the lower header into the low-pressure economizer, is heated in the economizer, and then enters the low-pressure boiler drum from the outlet header. The water in the low-pressure boiler drum enters the low-pressure evaporator through the downcomer, where it is heated to produce a steam-water mixture. The steam-water mixture enters the low-pressure boiler drum through the riser, where steam-water separation takes place. The separated saturated steam enters the low-pressure superheater, is heated in the superheater to form sub-low temperature hot steam, and then enters the low-pressure cylinder D of the turbine and the industrial gas interface E through the low-pressure main steam pipeline. Water in the low-pressure boiler drum is pumped by the high-pressure feedwater pump F and then enters the high-pressure economizer through a pipeline. After being heated in the high-pressure economizer, it enters the high-pressure boiler drum from the outlet header. Water in the high-pressure boiler drum enters the high-pressure evaporator through a downcomer. In the high-pressure evaporator, it is heated to produce a steam-water mixture. The steam-water mixture enters the high-pressure boiler drum through a riser, where steam-water separation takes place. The separated saturated steam enters the inlet header of the first high-pressure superheater. After being heated in the first high-pressure superheater, it forms superheated steam. It enters the inlet header of the second high-pressure superheater through the connecting pipe between the first and second high-pressure superheaters. After being further heated in the second high-pressure superheater, it enters the high-pressure cylinder C of the turbine through the high-pressure main steam pipeline to perform work.

[0020] The high-pressure main steam pipeline and the low-pressure main steam pipeline are connected by a pipeline. The pipeline is equipped with a shut-off valve 32 and a regulating valve 33. The flow rate and temperature requirements of the low-pressure main steam can be adjusted and controlled by adjusting the opening of the regulating valve 33 and the desuperheater 34, thereby adjusting the flow rate and temperature of the low-pressure main steam to meet the industrial steam demand.

[0021] The embodiments described above are merely preferred solutions of this utility model and are not intended to limit this utility model in any way. Other variations and modifications are possible without departing from the technical solutions described in the claims.

Claims

1. A dual-pressure gas turbine waste heat boiler with adjustable steam flow rate, comprising a boiler flue, wherein a high-pressure superheater II, a high-pressure superheater I, a high-pressure evaporator, a low-pressure superheater, a high-pressure economizer, a low-pressure evaporator, and a low-pressure economizer are sequentially arranged within the boiler flue; a low-pressure feedwater inlet is connected to the low-pressure economizer via a pipeline; the low-pressure economizer is connected to the low-pressure boiler drum; the water outlet of the low-pressure boiler drum is connected to the low-pressure evaporator via a downcomer; the low-pressure evaporator is connected to the low-pressure boiler drum via a riser; and the steam outlet of the low-pressure boiler drum is connected to the low-pressure... The superheater comprises a low-pressure superheater connected to the low-pressure cylinder of the steam turbine and the industrial gas interface via a low-pressure main steam pipeline; a low-pressure boiler drum connected to a high-pressure economizer via pipelines; a high-pressure economizer connected to a high-pressure boiler drum; a water outlet of the high-pressure boiler drum connected to a high-pressure evaporator via a downcomer; a high-pressure evaporator connected to the high-pressure boiler drum via a riser; a steam outlet of the high-pressure boiler drum connected to high-pressure superheater one; high-pressure superheater one connected to high-pressure superheater two; and high-pressure superheater two connected to the high-pressure cylinder of the steam turbine via a high-pressure main steam pipeline. Its characteristic is that... The low-pressure main steam pipeline is equipped with a desuperheater, and the high-pressure main steam pipeline is connected to the low-pressure main steam pipeline by a pipeline, which is equipped with a shut-off valve and a regulating valve.

2. The dual-compressor gas turbine waste heat boiler with adjustable steam flow rate according to claim 1, characterized in that, The low-pressure main steam pipeline is equipped with a check valve.

3. The dual-compressor gas turbine waste heat boiler with adjustable steam flow rate according to claim 1, characterized in that, The desuperheater is connected to the low-pressure water supply inlet.

4. A dual-compressor gas turbine waste heat boiler with adjustable steam flow rate according to claim 1, characterized in that, A high-pressure water pump is installed on the pipeline connecting the low-pressure boiler drum and the high-pressure economizer.

5. A dual-compression gas turbine waste heat boiler with adjustable steam flow rate according to claim 1, characterized in that, The boiler flue is connected to a chimney at its tail end.

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